Propagation of Hollyhock
- Plant seed out in the garden in an area where there is full sun to partial shade, in moist, fertile soil about one week before the last expected frost of the season. Place seeds just beneath the surface of the soil, spacing them about 18 to 36 inches apart. Seeds should germinate in two to three weeks after the soil reaches 60 degrees F.
- Plant seed in the garden in late August or early September when temperatures start to dip below 60 degrees. Protect seeds with a thick layer of mulch, or pile pine boughs on top. When temperatures warm up in spring, remove the pine boughs or some of the mulch, and they will sprout.
- Hollyhocks are prolific self-sowers. This means the seed falls to the ground in autumn, and next spring there may be twice as many stalks as there were the year before. In the fall, hollyhocks produce a brown seed capsule that has a papery husk. If left on the stalk, the husk breaks open and scatters seed that falls on the ground and grows in spring. To prevent this from happening, collect seedpods before they burst but are still dry and brown. Keep them in a sealed jar, and plant them the next spring or that same autumn in a desired area. Hollyhocks do cross-pollinate, so if there are several varieties in the garden, the flowers that bloom the next year may not be what you expect.
- Hollyhocks have very long taproots, so it is a little difficult to transplant or divide them. Dig up volunteer plants in the spring, preferably on a cool day, and replant them immediately.
Seed in Spring
Seed in Autumn
Self-Sowing
Transplanting
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